The phrase "theory of change" is a bit of jargon that I first encountered in the philanthropic and non-profit world, where it refers to a fairly new way of evaluating the effectiveness of projects by drawing out the underlying assumptions about how they lead to social change. It's a useful innovation, because often differences that seem to be about ideology or effectiveness are really just different ideas about the process that will lead to change, though unspoken and unquestioned. (For example, a foundation dedicated to ending hunger might choose between giving $100,000 to a food bank that feeds 100 people a day, or to a legal group that sues the state over Food Stamp eligibility rules, or to a national group that organizes poor people to push Congress for a total Food Stamp overhaul. At the end of a year, only the food bank would have results to show, but that doesn't mean it's the only effective approach -- the potential results from the other two approaches to change are much greater, if the legal and political strategies are sound.)

It's fascinating that this concept has become the key distinction in the Democratic presidential campaign. This is not a primary about ideological differences, or electability, but rather one about a difference in candidates' implicit assumptions about the current circumstance and how the levers of power can be used to get the country back on track. It's the first "theory of change" primary I can think of.

Hillary Clinton's stump speech is built around the speechwriter's rule of three, applied to theories of change: one candidate believes you achieve change by "demanding" it, another thinks you "hope for it," while she alone knows that you have to "work for it."

That's accurate as a rendering of the candidates' language: Her message of experience and hard work, Obama's language of hope and common purpose, Edwards' insistence that those with power will never give it up willingly. Paul Krugman weighed in Monday, mostly on the side of Edwards against Obama's "naive" expectation that by bringing all parties around a table, one could solve problems.

As an observer of politics, and commenter on it, I almost entirely share Krugman's and Edwards' diagnoses. I appreciate the conflictual nature of politics. I don't think there's some cross-partisan truth; I understand that the Republican conservatives are intractable. I know those advantaged by the current structure of power are determined to preserve it, and the well-funded campaign to destroy any possibility of progressive governance will be as intantaneous and intense as anything in 1993. I've tried to spell this out as clearly and aggressively as possible, especially to counter the tendency among elites to imagine that the good old days when Republicans and Democrats worked together selflessly and put ideology aside to solve the nation's problems are coming back. (Or that they were so great to start with.)

But let's take a slightly different angle on the charge that Obama is "naïve" about power and partisanship. Suppose you were as non-naïve about it as I am -- but your job wasn't writing about politics, it was running for president? What should you do? In that case, your responsibility is not merely to describe the situation exactly, but to find a way to subvert it. In other words, perhaps we are being too literal in believing that "hope" and bipartisanship are things that Obama naively believes are present and possible, when in fact they are a tactic, a method of subverting and breaking the unified conservative power structure. Claiming the mantle of bipartisanship and national unity, and defining the problem to be solved (e.g. universal health care) puts one in a position of strength, and Republicans would defect from that position at their own risk. The public, and younger voters in particular, seem to want an end to partisanship and conflictual politics, and an administration that came in with that premise (an option not available to Senator Clinton), would have a tremendous advantage, at least for a moment.

Any of the three "theories of change" has to be tested not just as a description of the current political situation, but as a tactic for breaking it. Even the non-naive Edwards believes that the structure of power can be broken -- by a large, engaged social movement. Clinton's theory in a sense takes the status quo for granted more than the others, but it's appropriate in certain situations: I imagine her negotiating the fine points of a health care bill, having mastered every lesson from 1993 and every detail, and getting Senators McConnell and Grassley in the room, and them walking out having agreed to something they barely understand. Superior knowledge and diligence can be a tool of power. Both are sound theories, both represent essential elements of change, but neither one is sufficient, or on its face more plausible than Obama's. While there will have to be a constituency for large-scale health reform (and thanks to the similarities in the Democratic candidates' proposals, there will be), there is no large-scale populist uprising on the horizon. And while hard work and mastery of details is also indispensable in a president, work alone does not overcome unyielding political opposition. As Karl Rove would say, it's not a "gamechanger."

So how might the Obama theory of change work? I'll give two answers, one entirely mundane and one a little cosmic. The mundane answer is just congressional math. The most important fact about the next administration is nothing about the president's character or policies, but simply how many Democratic Senators there are. To get health care passed in 2009, we'll need 60 votes in the Senate. There won't be 60 Democrats. So a Democratic president will need to, first, get within range by bringing in Democratic senators from Arizona, Colorado, Virginia, and several other red-trending-purple states. And then, subtract the total number of Democrats from 60, and that's the number of Republicans you'll need. If that number is two or three, almost anything is possible. If it's five, it will be much harder. If it's eight, impossible.

This is the math of bipartisanship. It's not a matter of sitting down with thugs like John Boehner and splitting the difference, but winning over just a few Senate Republicans from outside the South. And if the number is small enough, that's entirely possible. This is not 1993, when the Republicans could see that a majority was just around the corner, and the conservative takeover had given it a coherence and enthusiasm. It will be a party in some internal crisis after losing both houses of Congress and the presidency in short order, and the sense of a "party establishment" will be weaker. There will be an effort to hold the party together in united opposition, but the ties holding a Senator Snowe, Voinovich, Grassley, Lugar or Specter to a strict party line -- as they contemplate retirement, legacy, and their own now-Democratic states -- will be much weaker than in either the Clinton or Bush eras.

Obama's approach is better positioned to take advantage of this math. First, I think (though if I tried to prove it, I'd be relying on useless horse-race polls) that Democratic Senate candidates in red/purple states will do better with Obama's national-unity pitch at the top than with Senator Clinton. I worry about the Senate seats in Colorado (where she polls poorly) and Arizona with Clinton at the top of the ticket, and I think the opportunity to take out Mitch McConnell in Kentucky would be lost. And after the inauguration, I think that opposition to Hillary Clinton will remain a galvanizing theme for Republicans, whereas a new face and will make it harder to recreate the familiar unity-in-opposition.

Now for the cosmic explanation: What I find most interesting about Obama's approach to bipartisanship is how seriously he takes conservatism. As Michael Tomasky describes it in his review of The Audacity of Hope, "The chapters boil down to a pattern: here's what the right believes about subject X, and here's what the left believes; and while I basically side with the left, I think the right has a point or two that we should consider, and the left can sometimes get a little carried away." What I find fascinating about his language about unity and cross-partisanship is that it is not premised on finding Republicans who agree with him, but on taking in good faith the language and positions of actual conservatism -- people who don't agree with him. That's very different from the longed-for consensus of the Washington Post editorial page.

The reason the conservative power structure has been so dangerous, and is especially dangerous in opposition, is that it can operate almost entirely on bad faith. It thrives on protest, complaint, fear: higher taxes, you won't be able to choose your doctor, liberals coddle terrorists, etc. One way to deal with that kind of bad-faith opposition is to draw the person in, treat them as if they were operating in good faith, and draw them into a conversation about how they actually would solve the problem. If they have nothing, it shows. And that's not a tactic of bipartisan Washington idealists -- it's a hard-nosed tactic of community organizers, who are acutely aware of power and conflict. It's how you deal with people with intractable demands -- put ‘em on a committee. Then define the committee's mission your way.

Perhaps I'm making assumptions about the degree to which Obama is conscious that his pitch is a tactic of change. But his speeches show all the passion of Edwards or Clinton, his history is as a community organizer and aggressive reformer (I first heard his name 10 years ago because he was on the board of the Joyce Foundation in Chicago, which was the leading supporter of real campaign finance reform at the time), and he has shown extraordinary political skill in drawing Senator Clinton into a clumsy overreaction. If we understand Obama's approach as a means, and not the limit of what he understands about American politics, it has great promise as a theory of change, probably greater promise than either "work for it" or "demand it," although we'll need a large dose of hard work and an engaged social movement as well.